Main breakthrough After a day of probing, the goal of which was to determine whether German troops would choose to withdraw or not from the first set of trenches, the offensive started on 7 August 1943 at 06:30 (with a preliminary bombardment starting at 04:40) with a breakthrough towards
Roslavl. Three armies were committed to this offensive: the
5th Army, the 10th Guards Army, and the
33rd Army. The attack quickly encountered heavy opposition and stalled. German troops attempted numerous counterattacks from their well-prepared defense positions, supported by tanks, assault guns, and the fire of heavy guns and mortars. As
Konstantin Rokossovsky recalled, "we literally had to tear ourselves through German lines, one by one". On the first day, the Soviet troops advanced only , with all available troops (including artillery, communications, and engineers) committed to battle. Despite violent Soviet attacks, it quickly became obvious that the three armies would not be able to get through the German lines. Soviet commanders decided therefore to commit the 68th Army, heretofore kept in reserve, to battle. On the German side, three additional divisions (
2nd Panzer Division,
36th Infantry Division, and
56th Infantry Division) were sent to the front from the Oryol sector to try to stop the Soviet advance. The attack resumed the following day with another attempt at a simultaneous breakthrough taking place further north, towards Yartzevo. Both attacks were stopped by heavy German resistance. In the following five days, Soviet troops slowly made their way through German defenses, repelling heavy
counterattacks and sustaining heavy losses. By feeding reserve troops to battle, the Red Army managed to advance to a depth varying from by 11 August. Subsequent attacks by the armored and
cavalry forces of the 6th Guards Cavalry Corps had no further effect and resulted in heavy casualties because of strong German defenses, leading to a
stalemate.
Spas-Demensk offensive During the
Spas-Demensk Offensive Operation (Russian: Спас-Деменская наступательная операция) in the region of
Spas-Demensk, things went better for the 10th Army. The Wehrmacht had fewer troops and only limited reserves in this area, enabling the 10th Army to break through German lines and advance in two days. The 5th Mechanized Corps, relocated from
Kirov and committed to battle in order to exploit the breakthrough, failed in its mission, mainly because a poorly organized
anti-aircraft defense enabled Luftwaffe
dive bombers to attack its
Valentine tanks with some impunity. The corps sustained heavy losses and had to pull away from combat. Soviet troops eventually advanced a further as of 13 August, liberating Spas-Demensk.
Dukhovshchina offensive As ordered by the
Stavka (the Soviet
Armed Forces Command), the
Dukhovshchina-Demidov Offensive Operation near
Dukhovshchina started almost a week later, on 13 August. As on other parts of the front, the 39th Army and the 43rd Army encountered serious opposition. During the first day alone, Wehrmacht troops attempted 24
regimental-sized
counterattacks. Soviet troops managed to advance only over the next five days and, although they inflicted heavy casualties on Wehrmacht troops, their own losses were also heavy.
Causes of the stalemate By mid-August, Soviet operations all along the Smolensk front stabilized. The resulting stalemate, while not a defeat
per se, was stinging for Soviet commanders, who provided several explanations for their failure to press forward. Deputy Chief of General Staff General
A. I. Antonov reported "We have to deal both with forests and swamps and with increasing resistance of enemy troops reinforced by divisions arriving from Bryansk region" while Marshal
Nikolai Voronov, formerly a Stavka member, analysed the stalemate in his memoirs, publishing what he saw as the eight primary causes: • The Wehrmacht
OKH command knew about the operation and was prepared for it. • Wehrmacht
defense lines were exceptionally well prepared (firing points reinforced by
trenches,
barbed wire,
minefields etc.) • Several Red Army rifle divisions were insufficiently prepared to perform an assault of a multi-lined defense setup. This was especially true for reserve divisions, whose training was not always properly supervised. • There were not enough tanks committed to battle, forcing Red Army commanders to rely on artillery,
mortars, and
infantry to break through Wehrmacht lines. Moreover, numerous counterattacks and an abundance of minefields slowed the infantry's progress. • The interaction between
regiments and
divisions was far from perfect. There were unexpected pauses during the attack and a strong will of some regiments to "hide" from the attack and expose another regiment. • Many Red Army commanders were too impressed by Wehrmacht counterattacks and failed to act properly, even if their own troops outnumbered those of the Wehrmacht. • The infantry were not using their own weapons (such as their own heavy guns and portable mortars) well enough. They relied too much on artillery. • The fact that the offensive was postponed from 3–7 August gave German troops more time to increase their readiness. With all these factors considered,
Voronov demanded that the
4th Tank Army and the
8th Artillery Corps be transferred from the
Bryansk Front and committed to support the attack near Smolensk. The stalemate was far from what had been desired by the Stavka, but it had at least one merit: it tied down as much as 40% of all Wehrmacht divisions on the
Eastern Front near Smolensk, making the task for troops fighting in the south and near
Kursk much easier. The Stavka planned to resume the offensive on 21 August, but decided to postpone it slightly to give Soviet units time to resupply and reinforce. ==Second stage (21 August – 6 September)==